well I start off with a mejai soulstealer( its good if you are smart enough to gank wisely) and then its all like you said, I add a RoA too.
Now as for ad poppy she wont hit that hard .She may have continuous dmg output but when you want to get the enemy carry out ap is better .
I tried both too
I will come back with some screenshots and some math calculations for ap poppy to show an average dmg output